Multimedia capabilities can be incorporated into a wide range of devices, including digital televisions, digital direct broadcast systems, wireless communication devices, personal digital assistants (PDAs), laptop computers, desktop computers, digital cameras, digital recording devices, cellular or satellite radio telephones, and the like. Digital multimedia coding can provide significant improvements over conventional analog systems in creating, modifying, transmitting, storing, recording and playing full motion multimedia sequences. Broadcast networks, for example, may use multimedia coding to facilitate the broadcast of one or more channels of multimedia sequences to wireless subscriber devices. Broadcasting techniques used in such broadcast networks include those referred to as Forward Link Only (FLO), Digital Multimedia Broadcasting (DMB), and Digital Video Broadcasting—Handheld (DVB-H).
Digital multimedia broadcasting typically relies on one or more digital multimedia encoding standards. A number of different multimedia coding standards have been established for coding digital multimedia sequences. The Moving Picture Experts Group (MPEG), for example, has developed a number of standards including MPEG-1, MPEG-2 and MPEG-4. Other standards include the International Telecommunication Union (ITU) H.263 standard, QuickTime™ technology developed by Apple Computer of Cupertino Calif., Video for Windows™ developed by Microsoft Corporation of Redmond, Wash., Indeo™ developed by Intel Corporation, RealVideo™ from RealNetworks, Inc. of Seattle, Wash., and Cinepak™ developed by SuperMac, Inc. Furthermore, new standards continue to emerge and evolve, including the ITU H.264 standard and a number of proprietary standards. The ITU H.264 standard is also set forth in MPEG-4 Part 10, entitled “Advanced Audio Coding.”
A variety of other coding techniques have also been developed. For example, interpolation techniques (sometimes referred to as Frame Rate Up-Conversion (FRUC) techniques) have been developed to interpolate additional frames between transmitted multimedia frames in order to increase the effective frame rate of a multimedia sequence on the decoder side. Also, scalable coding approaches have been developed in which multimedia frames are transmitted as a base layer and one or more enhancement layers. Scalable coding can be used to provide signal-to-noise ratio (SNR) scalability, temporal scalability, and/or spatial scalability in multimedia compression applications. The base layer carries a minimum amount of data necessary for multimedia decoding, and provides a base level of quality. The enhancement layer carries additional data that enhances the quality of the decoded multimedia sequence, but may have a higher packet error rate than the base layer and/or require a higher signal-to-noise ratio (SNR) to achieve the same packet error rate. These techniques, including interpolation techniques and/or scalable video coding techniques, may be used with or without compliance with the coding standards listed above.